In general, a turbine refers to a machine or an apparatus for converting energy included in fluid, such as water, gas, or steam, into useful mechanical work. An apparatus for generating energy by using such a turbine is mainly used in tidal power generation. In conventional tidal power generation, a tidal dam is built in a back bay, where there is a big difference between the ebb and flow of the tide, to thereby interrupt the movement of sea water, and then electricity is generated using the difference between water levels inside and outside of the tidal dam, which is caused by the difference between the ebb and flow of the tide. This mechanism of tidal power generation is similar to that of hydroelectric power generation.
However, since conventional tidal power generation is driven using potential energy, it requires a water level above a certain height. To this end, it is requisite to build a seawall, which is accompanied by environmental problems including sea water pollution.
To solve these problems, a helical turbine was developed by Professor Alexander M. Gorlov of Northeastern University, USA, and is currently in use. The helical turbine is an apparatus capable of providing rotation under multidirectional fluid flow, as well as unidirectional fluid flow. As illustrated in FIG. 1, such a helical turbine generator includes a frame 120 dipped in fluid, a housing supporter 110 provided in the frame 120 and forming an inner cylindrical space, a housing assembly 140 inserted and fixed in the housing supporter 110, and a helical turbine 130 rotatably mounted in the central portion of the housing assembly 140.
The helical turbine 130 includes a rotating shaft 131 rotatably supported by the housing assembly 140, a plurality of supporting members 132 radially protruding from the rotating shaft 131 while being arranged in layers along the rotating shaft 131, and a blade 133 connected to distal ends of the respective layered supporting members 132, having a streamlined cross section, and helically twisted in the longitudinal direction of the rotating shaft 131.
Also, the housing assembly 140 is inserted and fixed in the inner receiving space of the housing supporter 110.
In the conventional helical turbine generator having the above structure, however, there is a problem in that when the housing assembly 140 supporting the helical turbine 130 is assembled in the inner space of the housing supporter 110, a rotational force continuously acts on the helical turbine 130 due to fluid flow, even during the assembly process, and consequently the housing assembly 140 is rotated in the inner space of the housing supporter 110 by the force applied to the helical turbine 130, which makes it difficult to assemble the housing assembly 140.
Further, when the helical turbine 130 is damaged or worn out during its use, and thus the helical turbine 130 and the housing assembly 140 need to be disassembled from the housing supporter 110, it is also difficult to disassemble the helical turbine 130 and the housing assembly 140 because the helical turbine is continuously rotated.
Further, there is a problem in that weakenings having low strength are generated in the process of assembling the housing assembly 140.